| Popis: |
PM2.5 samples were collected at a roadside site in Wuhan, China, for one year period. Ion chromatography was used to determine the water soluble ions in PM2.5 samples. Results showed that the overall average of PM2.5 mass was 118.1 ± 70.3 μg m−3, being slightly higher than those measured in urban sites in Wuhan, China. The major water soluble ions were NH4+ (8.7 ± 4.0 μg m−3), NO3− (12.1 ± 9.5 μg m−3), SO42− (15.2 ± 8.2 μg m−3), accounting for 21%、29%、37% of quantified total ions, respectively. NH4+, NO3−, and SO42− were closely correlated, and (NH4)2SO4 and NH4NO3 were possibly their main existing forms. Ion concentrations differed greatly in different seasons, with inconsistent variation pattern for individual ions. Values of NOR (nitrogen oxidation ratio) and SOR (sulfur oxidation ratio) peaked in winter and in summer, respectively. NO3−/SO42− ratio revealed that emission from stationary sources was still remarkable. Significant correlation was observed between Mg2+ and Ca2+, possibly due to their common source of soil dust. On the other hand, Cl− linked with K+, NO3−, NH4+, and SO42−. The data reported here will provide inputs for human exposure and air pollution control studies in Wuhan, China. |
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